Foul Smell from Blower / Fan / HVAC

K a s h · 29th April 2008, 12:00

Quote:

Originally Posted by alankarmotor

HI, as i have replied to this thread earlier , you will notice this smell comes only when the blower is not used at max speed mode, this happens because the reduction in blower speed is achieved by using resistance in the circuit. This resistance becomes very hot when blower is used at low speeds so when the A/C is on resistance gets cooled continuously ,but as soon as you switch off the A/C the temp. of the resistance increases , the resistance coil of wires are held together by a special ceramic material which is a bad conductor of heat ,it is heating up of this ceramic material which gives this bad smell.Cars which dont have this kind of resistance will not have this probelem ,like ZEN,FORD IKON ,OPEL etc.

Hi AlankarMotor,
Can you please elaborate on what must be done to fix this issue? Just curious to know if this can be done by ourselves.

m-hawk · 5th May 2008, 21:23

Quote:

Originally Posted by alankarmotor

HI, as i have replied to this thread earlier , you will notice this smell comes only when the blower is not used at max speed mode, this happens because the reduction in blower speed is achieved by using resistance in the circuit. This resistance becomes very hot when blower is used at low speeds so when the A/C is on resistance gets cooled continuously ,but as soon as you switch off the A/C the temp. of the resistance increases , the resistance coil of wires are held together by a special ceramic material which is a bad conductor of heat ,it is heating up of this ceramic material which gives this bad smell.Cars which dont have this kind of resistance will not have this probelem ,like ZEN,FORD IKON ,OPEL etc.

WOW this make s sense but if that was so simple then why havent the resistance circuit upgraded to face this smelly problem !!
EVen not using recycling mode and not letting leaves and dust enter does nt sound so convincing !! Infact when your car is hot as a furnace and you need effective cooling the best way is to let fresh air in an let the hot packed air be pushed out but being behind exhaaust s at traffic signal s spiral s the problem with diesel smoke smell in the cabin !!!

ganeshanayak · 5th July 2008, 14:02

I have read quite a many complaints from this website about the problem of "bad smell" from A/C. Personally, I was shocked by seing this problem with my Honda City. When discussed this with the dearler (Whitefield Honda, Bangalore) they too agreed and said they will forward the complaint to Honda Japan :-)
As a solution, the person who attended my car advised to keep the blower ON (with A/C off) for 2-3 minutes just before switching off the car. This solution was quite sensible after I got to know that the A/c smell is due to the fungus (I think some dentist has mentioned about this somewhere)
Note that, I have tried myself that the "foul smell" disappears when blower is kept ON for few minutes (2-3 min) with HEATER option ON before switching off the car. Next morning my car is good. This is about the solution part.
But I would expect the Honda guys should be able to find the root cause for this. I don't think this problem exists in other high end cars like Merc, BMW, Audi etc.

SO, WHY HONDA CAN NOT FIX THIS ?

varunroy · 5th July 2008, 16:31

It could also happen if a tiny Rat has gone into the air inlet flap that let in fresh air into the AC blower for circulation. This oneway flap is so designed that it is easy for anything to go in but coming out is almost impossible. This happen to a friend of mine owning a Zen. She kept complaining about this fishy smell to MASS. Those guys went over the car on more than 3 occassions but could not settle the issue.

I happened to talk to my tinker about it and he told that there's a dead rat in the blower unit. I took the car to him and in less that an hour our man pulls out the fragmented remains of what could have been a Mouse. The job was done for 500 bucks. The poor girl has spent a fortune on room freshners all this while.

If anyone in Bangalore has this problem, send me a PM.

So long....

HKS · 29th May 2009, 20:58

Guys, its the mildrew growing in moisture conditions in your A/c. There is one very simple solution. Turn off the A/c and run the car with full speed fan for a couple of kms or so to dry it out.

Cheers.

If it isn't solved yet, let me know.

PS: This is the solution when you turn on your A/C fan and you get the odour.

gpa · 30th May 2009, 12:43

Quote:

Originally Posted by HKS

Guys, its the mildrew growing in moisture conditions in your A/c.

The best solution to this is to use an AC neutralizer. Gulf sells cans of this and one can DIY it at home. Removes all pungent odours and cleans the system of germs and mildew. Have used it and will recommend it

Cheers,
gpa

HKS · 30th May 2009, 13:03

Yes, the solution I have mentioned also works out well.

GPA whats the can called?

gpa · 31st May 2009, 13:27

Quote:

Originally Posted by HKS

GPA whats the can called?

The product is called - Gulf AC Neutralizer. Retails for about Rs. 200 in outlets like Spar.

sabret00the · 31st May 2009, 14:14

Even I face the same problem. The distance I travel everyday has mostly dusty roads due to construction activities. Whenever I turn off my A/C and just let the blower run it emits a "DUSTY" smell. The same smell disappears once the A/C is turned ON. I was told by MASS that the entire A/C system needs to be overhauled to take care of this issue and it's going to cost extra apart from normal service charges so I didn't bother to address it. Now whenever I travel through extremely dusty roads I turn off the blower and A/C.

ajitsank · 11th July 2009, 21:13

I own a March 2009 Swift ZXI, few weeks back I noticed that mid way through the drive I get a suffocating smell/odor in the car. The suffocation so much so that the people seated in the front including the person driving the car feels a burning sensation in the nose. Surprising this is there only for few minutes and then it is gone without a trace.

The Air circulation is set to cabin circulation, I tried few of the things mentioned below;

1. Removed the in-car perfume
2. Driven the car for few KM with the air intake set to from outside

Nothing seems to get rid of this. The car is cleaned every day, both inside and outside so there is no dust or other particles inside/outside the car.

srikant · 12th July 2009, 08:52

You better take the car to MASS ans get your blower pipes checked.This may be caused by some thing blocked in the pipes.

gpa · 12th July 2009, 15:09

From what you have explained, seems like this happens frequently but the burning smell and odur only stays for a little while. Could be something stuck in the vents as well.

watashi75 · 13th August 2009, 08:59

I have been facing similar problems in my Swift. I usually drive with a/c all the time in recirculation mode. When the blower speed is less there is a peculiar burning smell but not really unpleasant. When I increase the blower speed the smell goes away. If I reduce the blower speed the smell returns again.

However it does not happen on all days. Maybe it depends on the temperature and humidity but I have not tried experimenting that. I tried opening the hood after such a drive but I did not observe any smell there.

I used to suspect earlier that it might be a slipping clutch. But the service guys said that the clutch is good.

shankar.balan · 13th August 2009, 09:30

interesting - where do you spray it exactly?
will you give me some details?
would like to pick this up and use it just for regular maintenance
thanks

Quote:

Originally Posted by gpa

The best solution to this is to use an AC neutralizer. Gulf sells cans of this and one can DIY it at home. Removes all pungent odours and cleans the system of germs and mildew. Have used it and will recommend it

Cheers,
gpa

gpa · 13th August 2009, 11:57

Quote:

Originally Posted by shankar.balan

interesting - where do you spray it exactly?
will you give me some details? would like to pick this up and use it just for regular maintenance
thanks

shankar,

You get a long thin tube type attachment with the bottle of spray. You have to insert it into the the opening of the a/c vents till the tube goes deep inside and then spray the contents of the can deep inside.

A white foam soon starts to form and will come to the opening of the vents. It does help if you can close the vents shut during the process and then open them after about 15 mins and let the blower run on the lowest speed for about 5 mins.

There is a detailed DIY with photos by one of our member is the modifications and accessories section and you can check that thread for more info.

Hope this helps.

Cheers,
gpa

5th July 2008, 14:02	#138
ganeshanayak Newbie Join Date: Jul 2007 Location: Bangalore Posts: 2 Thanked: 0 Times	foul smell from car AC - a simple solution I have read quite a many complaints from this website about the problem of "bad smell" from A/C. Personally, I was shocked by seing this problem with my Honda City. When discussed this with the dearler (Whitefield Honda, Bangalore) they too agreed and said they will forward the complaint to Honda Japan :-) As a solution, the person who attended my car advised to keep the blower ON (with A/C off) for 2-3 minutes just before switching off the car. This solution was quite sensible after I got to know that the A/c smell is due to the fungus (I think some dentist has mentioned about this somewhere) Note that, I have tried myself that the "foul smell" disappears when blower is kept ON for few minutes (2-3 min) with HEATER option ON before switching off the car. Next morning my car is good. This is about the solution part. But I would expect the Honda guys should be able to find the root cause for this. I don't think this problem exists in other high end cars like Merc, BMW, Audi etc. SO, WHY HONDA CAN NOT FIX THIS ?
	() Thanks

5th July 2008, 16:31	#139
varunroy BHPian Join Date: Oct 2005 Location: Bangalore Posts: 385 Thanked: 14 Times	It could also happen if a tiny Rat has gone into the air inlet flap that let in fresh air into the AC blower for circulation. This oneway flap is so designed that it is easy for anything to go in but coming out is almost impossible. This happen to a friend of mine owning a Zen. She kept complaining about this fishy smell to MASS. Those guys went over the car on more than 3 occassions but could not settle the issue. I happened to talk to my tinker about it and he told that there's a dead rat in the blower unit. I took the car to him and in less that an hour our man pulls out the fragmented remains of what could have been a Mouse. The job was done for 500 bucks. The poor girl has spent a fortune on room freshners all this while. If anyone in Bangalore has this problem, send me a PM. So long....
	() Thanks

29th May 2009, 20:58	#140
HKS BHPian Join Date: Mar 2008 Location: Mumbai Posts: 104 Thanked: 6 Times	Guys, its the mildrew growing in moisture conditions in your A/c. There is one very simple solution. Turn off the A/c and run the car with full speed fan for a couple of kms or so to dry it out. Cheers. If it isn't solved yet, let me know. PS: This is the solution when you turn on your A/C fan and you get the odour.
	() Thanks

30th May 2009, 13:03	#142
HKS BHPian Join Date: Mar 2008 Location: Mumbai Posts: 104 Thanked: 6 Times	Yes, the solution I have mentioned also works out well. GPA whats the can called?
	() Thanks

31st May 2009, 14:14	#144
sabret00the BHPian Join Date: Mar 2006 Location: YYC \| BLR \| CCU Posts: 691 Thanked: 55 Times View My Garage	Even I face the same problem. The distance I travel everyday has mostly dusty roads due to construction activities. Whenever I turn off my A/C and just let the blower run it emits a "DUSTY" smell. The same smell disappears once the A/C is turned ON. I was told by MASS that the entire A/C system needs to be overhauled to take care of this issue and it's going to cost extra apart from normal service charges so I didn't bother to address it. Now whenever I travel through extremely dusty roads I turn off the blower and A/C.
	() Thanks

11th July 2009, 21:13	#145
ajitsank BHPian Join Date: Aug 2007 Location: Secunderabad Posts: 122 Thanked: 24 Times	Swift Zxi Ac Problem I own a March 2009 Swift ZXI, few weeks back I noticed that mid way through the drive I get a suffocating smell/odor in the car. The suffocation so much so that the people seated in the front including the person driving the car feels a burning sensation in the nose. Surprising this is there only for few minutes and then it is gone without a trace. The Air circulation is set to cabin circulation, I tried few of the things mentioned below; 1. Removed the in-car perfume 2. Driven the car for few KM with the air intake set to from outside Nothing seems to get rid of this. The car is cleaned every day, both inside and outside so there is no dust or other particles inside/outside the car.
	() Thanks

12th July 2009, 08:52	#146
srikant BHPian Join Date: Jul 2008 Location: Bengaluru Posts: 489 Thanked: 12 Times	You better take the car to MASS ans get your blower pipes checked.This may be caused by some thing blocked in the pipes.
	() Thanks

12th July 2009, 15:09	#147
gpa Senior - BHPian Join Date: Aug 2008 Location: Bangalore Posts: 1,790 Thanked: 345 Times	From what you have explained, seems like this happens frequently but the burning smell and odur only stays for a little while. Could be something stuck in the vents as well.
	() Thanks

13th August 2009, 08:59	#148
watashi75 BHPian Join Date: Jan 2008 Location: Hyderabad Posts: 518 Thanked: 13 Times	I have been facing similar problems in my Swift. I usually drive with a/c all the time in recirculation mode. When the blower speed is less there is a peculiar burning smell but not really unpleasant. When I increase the blower speed the smell goes away. If I reduce the blower speed the smell returns again. However it does not happen on all days. Maybe it depends on the temperature and humidity but I have not tried experimenting that. I tried opening the hood after such a drive but I did not observe any smell there. I used to suspect earlier that it might be a slipping clutch. But the service guys said that the clutch is good.
	() Thanks